updated: approx relative masses distances
Code:
nearest distance
Earth: 6000000000000000000000000 kg
Moon: 74000000000000000000000 kg 0.0026 a.u.
ELENIN: 6350293180 kg 0.03 a.u
Haley's comet: 220000000000000 kg 0.03 a.u
the gravitational effect is proportional to mass and to the inverse square of distance (it gets weaker quickly as you increase distance)
in other words,
elenin, at its closest, has about 1 / 1165300528691495 the gravitational effect the moon has all the time.
Edit: it would be like someone parked the titanic on the moon for a couple days.